L1 - What is Food? Flashcards
What 2 main classes can nutrients be divided into?
Macronutrients and micronutrients
What are the macronutrients? Why are they called this/
Protein, carbohydrates and lipids
They are needed in large amounts
What are the micronutrients? Why are they called this?
Vitamins and minerals
They are needed in much smaller amounts than macronutrients
How many amino acids are there? How many are essential in the majority of species?
23 AAs, 9 essential
Why are some amino acids essential?
They can not be produced at a sufficient rate, so need to be taken in through the diet
What are the major differences between some species in terms of which amino acids are essential/non-essential?
Cats - taurine is essential
Humans - arginine is non-essential
What are the 4 major classifications of carbohydrates?
Absorbable, digestible, fermentable and non-fermentable
What are the absorbable carbohydrates?
Monosaccharides (e.g. glucose)
What is blood glucose levels regulated by?
Insulin
What is glucose stored as in the body?
Glycogen
What is ketosis in pregnant or lactating cows and sheep? How does this occur?
An increase in ketone production - if less glucose is eaten, more fat is burned which leads to excess ketones
What are the digestible carbohydrates?
Sugars (disaccharides) and starch (polysaccharide)
What are the fermentable carbohydrates?
Oligosaccharides, resistant starch, non-starch polysaccharides
What are the non-fermentable carbohydrates? What do these do?
Insoluble fibre - increases gut motility and reduces constipation
What types of lipid are there?
Saturated, monounsaturated and polyunsaturated
What type of lipid is solid at room temperature?
Saturated
What are the essential fatty acids?
Linoleic, alpha-linolenic, and arachiadonic acids
How much energy (in kcal/g) do each of the macronutrients provide?
Protein and carbs - 4.1 kcal/g
Lipids - 8.8 kcal/g
How many vitamins are there? What are they?
19 - A, B complex (14), C, D, E, and K
How can vitamins be classified?
What vitamins belong to each category?
Water soluble - B and C
Fat soluble - A, D, E, K
What type of vitamin needs to be taken in regularly?
Why is this?
Water soluble - the are stored poorly in the body compared to fat soluble vitamins, and excesses are lost in urine
What is the alternative name for vitamin A?
Retinol
What is the major source of vitamin A?
Carotenoids such as beta-carotene from plants
What are the major sources of B complex vitamins?
Bacteria in gut - rumen, caecum or LI
Ingestion of soil
What B vitamin plays an important role in pregnancy?
B9 - folic acid
What is the alternative name for vitamin C?
Ascorbic acid
What cells are high in vitamin C?
Immune cells (deplete during infection)
What animals cant produce their own vitamin C?
Primates, bats, guinea-pigs and capybaras
What is the alternative name for vitamin D?
Calciferol
What is the role of vitamin D?
Calcium absorption
How is vitamin D synthesised?
UVB converts cholesterol in skin to vitamin D
What is the alternative name for vitamin E?
Tocopherol
Give 2 major functions of vitamin E
- Antioxidant - incorporated into cell membranes to prevent oxidative damage
- Enzyme regulation
- Neurological functioning
- Gene expression
What is the role of vitamin K?
Regulates formation of blood clotting factors
What vitamin is given as an injection to newborns? Why is this?
Vitamin K - prevents serious bleeding before the body has made sufficient amounts of blood clotting factors
